Pretending to be rich was historically important. And it seem to be important still. Just recently I have seen a study showing, that about 40 percent of people in the US making more than 500k a year are living paycheck to paycheck.
It makes complete sense if you think about you need (do not really need but you try) to stay at the level of your peers and those above to impress them.
We tend to meet with the people of our own social group and rarely go grab a drink with a homeless guy or a multimillionaire. That is also why being richer for many people does not mean more freedom but more expenses.
But why should not you have fun with someone who is poorer? It will benefit both them and you.
In the past meeting with different social classes was bad because of the rigid division of nobility and peasants. Nowadays this does not apply in most countries.
And yes, your social group might look at you weird if you do not try to keep up with them, but so what? Do you really need to be “friends” with them?