I've made no real sacrifice with the Scion. It's made by Toyota and is a very high quality, dependable car. It will serve me well for many years. That's all a car needs to be in my eyes.
For things that are important to me, sure, I buy the best I can afford. But only a very small number of things are truly important to me. I suppose my definition of minimalism is just truly getting what you need, nothing more or less. I feel no need to "keep up with the Jonses", and overall just don't feel compelled to "be a good consumer".
I agree a minimalist lifestyle is not necessarily a cheaper lifestyle. I totally agree with that. But I do feel a minimalist lifestyle can be cheaper if your desires and needs just happen to work out that way, which in my case I generally feel they do.
I try to live my life in a 'minimalist' way, because I feel less clutter makes for a more serene life. Still, making money is quite important to me, if only for the security it represents. On the other hand I also sometimes wonder if I'm spending enough to optimize life joy; I drive a small Citroen Saxo but I'm regularly annoyed by the small amount of space in it, and the inconvenience that it has only 3 doors. I guess my point is that it's surprisingly hard to walk the line between stinginess (a generally negative trait) and minimalism (a generally positive trait).
BMW drivers are often happier (driving) than other drivers, and more relaxed (and by extension, a bit safer) in their cars than drivers of other brands. The effect of satisfaction, quality, and usability is not well understood but we do know it's significant.
I'm an amateur photographer, and I do know that I take better pictures on some cameras than others. On the el-cheapo digital SLRs, I find that the small size, the poorer button placement, the lack of a satisfying weight to the contraption, etc, all lends itself to annoyance. A quality camera feels right in the hand, has just the right weight to it, and feels good to use, and that does impact the things you do with it.
A lot of what people in this thread would qualify as "excessive luxury" IMHO is not as irrelevant and excessive as one would think at first glance.
On the point about the cameras. If the photographer has a decent level of talent, then the gear definitely matters. Less so if they don't.
I know a lot of gadgety people who like to show off their expensive cameras. Their photos, however, aren't worth showing off at all - it wouldn't have mattered if they used a 5DMK2 or a lowly Rebel XSi. Boring is still boring no matter how sharp the picture is.
Whereas if I drove every day, and would spend a lot of time in the driver seat, I'd be much more inclined to buy something nicer (as opposed to merely functional).
In this case, photography is important to me, and I spend a lot of time doing it - so it's important that I have a tool that not only works well, but feels satisfying to use. After all, it's not a very good hobby if I'm constantly being frustrated by my equipments' usability.
Likewise, it's important for me to have a really nice coffee mug - given that it's part of my daily routine and I spend a lot of time interacting with it.
What I see is that many people over-optimize and fail to account for this effect - and they skimp on things that they do use heavily, resulting in a quality of life loss that they're probably not even aware of. (e.g., daily commuters, people who spend tens of hours in a car weekly, but driving a "good enough" beater, when they can easily afford better... or hackers who buy cheap/poorly made keyboards/mice even though they spend hours with it every single day).
This is not a good example of minimalism and in contradiction with your earlier statement that "Frugal implies you are sacrificing quality or desire in the name of money" (I infer you were contrasting with minimalism here)
A BMW is a lot higher quality than cheap cars, not necessarily 'excessive luxury'. It can be simple, depending on the configuration. One can find minimalist joy in a very expensive BMW. 'Just getting to the grocery store' is not about minimalism, it's about frugality. It's not because something is expensive that it's 'excessive'. Actually simple, high-quality products are often more expensive then cheap trinkets. To have a lot of leeway, one leads a frugal lifestyle to save money. A minimalist lifestyle isn't necessarily a cheap lifestyle.