What are your thoughts on resellers?

So I just thought I'd bring this question up since I chatted online with a socialist I told him I used to be a toy reseller on ebay when I was 17 (now 19) and made 1000s of dollars.

It was hard work for me with high school AP classes and managing ebay and I had no support except myself spend hours shopping and shipping.

I'm now off eBay as I grew a lot less passionate about it (thank you ADHD) but what this chatter told me was that I hurt poor people by doing this because I was to thrift stores and clearance sections and buy up all the stock. He told me that I was part of the reason boys and girls wouldn't be having toys for Christmas. He also told me I'm just one of the toxic elements of capitalism.

And...he's right. I mean I did go to the stores. But at the same time I'm doing the job for the market.

I buy a nerf gun for $20 and I sell it to another person who values the gun at $50 so...markets 🎊

Is it unethical to resell? Are there certain goods that shouldn't be resold?

Like I understand reselling hand sanitizer during a global pandemic to be entirely unethical but toys I mean really.