I can't see how. You're not scraping, not stealing code, not doing anything. You're just checking them out (and they will likely check you out).
Auto companies tear down each others cars. Tech companies tear down each others products. Grocery stores check out each others prices.
and so and so on.
None of them steal. Just poke, prod, look, and learn. Then apply to their own if it's suitable.
I have never seen a Non-compete clause in any TOS.