How to unspoil a child who is being spoiled

Need some parenting advice mamas!

I have an amazing step son who is 10! He is very mature and wise for his age... but he is also spoiled and a “know it all”.

I grew up in a lower economic class family. In no way did we ever go hungry, but school clothes shopping was a trip to the goodwill and Salvation Army store. This really molded who I am today and has made me extremely grateful for everything I have.

My 10 year old’s mother is VERY well off. They live in a million dollar home, only drive the newest cars, so my son gets EVERYTHING he wants. He spends most of his time on Amazon filling his moms cart with new shoes, PlayStations, game controllers, hover boards, etc. And she gladly gets it all for him.

He has become very spoiled and entitled, the exact person I don’t strive to be around in my life which breaks my heart. I have tried to make small comments here and there on why he should be grateful for what he already has and how he doesn’t need the newest or coolest item, but he just laughs in my face.

Is this something I can change? If so, how? I feel like I am in an uphill battle as he continually gets spoiled when he is at his moms. Not to mention I have to walk on egg shells because his mom doesn’t want me to help “parent”. I just don’t want my 10 year old to be a rich bully. I already see him making fun of people for their clothes and their shoes. I immediately nip it in the butt, but he doesn’t learn and is back at it a day or two later. Again, I am limited on how I can discipline.

I have also tried talking to my husband but he doesn’t see it or chalks it up to “he was just kidding”