I use it as leverage at performance review time. Non-emotional, but “hey I like working here and contributing to the goals of company x, but I want you to know I’ve received an offer for $z. I believe that’s a fair evaluation of my market rate. I’d like to see a commitment from (current employer) that matches that in the near future. Do you think that is workable?”

You clearly need to be someone your manager is willing to fight HR in order for this to work. But it’s been effective for me.

If money is more important to you than the culture/non-monetary things the current job offers, then leave. You can try bringing it up to your manager and get into a higher position, where a raise would be appropriate, but when people try to leverage other positions against our business for higher salary, I deny them 100% of the time unless we are talking about a promotion that makes sense.

"culture" doesn't put food on the table, or pay the rent. As the old saying goes: "fuck you, pay me."

This is true generally. But the difference in money has to be appreciable. You wouldn't leave a job you loved for $5 extra per year. You might for $50k.

The people that want it both ways are stuck, generally. You can't like the job you are at and also demand more money if you aren't willing to leave. BATNA and so forth.

While I kind of agree, culture is essential. I have the feeling for some people there is no cultural fit in any company.

While I liked some people at some companies, I never liked company cultures. So I based decision there on the kind of work I had to do and the payment.

It depends how confident / you are with the relationship with your boss. If they are someone you can tell that you are seeing way more money elsewhere, then you may want to tell them. If you are uncertain you could be taking a gamble, but if they are looking to replace you, you may not want to work there anyway.