Note that you might want to check if hosting in Germany has any legal implications for you - German data protection laws are vastly more strict than the US, say.
1. The company is so un-automated that it actually needs considerable human intervention to prepare a server and doesn't actually bother to include this basic operation into their total cost (they sell servers after all).
2. It's a trick to squeeze at least the 150 euro from you. Because if I find out in the first months that their service is sub-par I can just cancel my subscription but I'm not getting my 150 euro back.
Serious hosts will give you free trials (before you pay the setup fee) any time, unless you ask for special hardware that they themselves have to buy first.
Personally, I address this by having pre-payment discounts. cover your account for a year and I knock off 20% (and usually use the cash to go buy a new server) - I also allow people to sign up and pay monthly (at a higher rate, of course) but with my current price /discount setup, the majority of my income is from pre-paid customers.
Perhaps setup fees /kinda/ make sense if you are some high-quality name in the business and people will know they are staying long-term. But if I see a well-known company without setup fees and your company with a setup fee it won't take long to decide.
What you mentioned is far more decent: a bonus for payment in advance but I don't see how they expect to charge me the equivalent of 3 months in advance just to test them out.
Really, it's less about margin, though, and more about credit. If I had more, it wouldn't really matter... but I don't, so it does.
for a while I was renting out whole servers at nearly co-lo rates... with the catch that the customer needed to pay a setup fee that would cover the parts cost of the server up front.
It was pretty popular, actually; I only stopped doing it because it put me in a bad place as a provider... thing of it is, sometimes you really do need to fire your customers. I don't want to be in a position, though, where I get a bonus for firing my customers.
That way you pay 103 EUR/mo (about 134 USD) and skip a lot of headache.