In fact, AFAIK he keeps them: I buy in a little local store owned by another crypto enthusiast. I pay him P2P via LN using Wallet of Satoshi, and I think that I am the only customer who pays him this way.
In that case, it's ok. The two of you have a private deal where you pay with crypto and receive your groceries. I had something completely different in mind the first time I read your post. I thought It's one of those shops that accepts crypto payments on the counter, where they provide you with the address to pay. In most cases, such shops use a payment processor that converts the crypto assets into fiat upon receipt. Since you are sending to the owner from your private wallet to his, there is no fear of anyone asking any questions.
The only danger is if the coins go directly from you into a centralized exchange that might not like your use of Wasabi. But that's also not happening, so you are fine.