AITAH for thinking my cousin is cheap?

I got married recently. I didn't expect any wedding gifts whatsoever because we eloped, but our loved ones have been so generous in giving us some cash gifts.

So, with that, I feel so icky about this, but the thought keeps popping into my head, so I have to ask AITAH....

My cousins (two brothers, both married with kids) each gave us an envelope with cash. Both brothers gave the same amount, $500.

Younger cousin's household income: $180k

Older cousin's household income: $550k

My household income: $120k

I know this is so icky, but the thought keeps entering my head that my older cousin is so cheap!

$500 is the amount I give to close friends and family when they get married -- but our household income is less than 1/4th of theirs, and we have a higher cost of living (we live in a big city, fairly centrally). Both brothers live in the suburbs of a small city.

This same cousin goes on expensive vacations every year and invites us, and we decline, letting him know that it's not feasible for us financially... and then he keeps asking us to come!

So, AITAH for even having this thought? Maybe someone in a similar tax bracket to my older cousin can help me understand.