I'm generally strongly in favour of bare metal (not so much actually on prem) but your case is one of the rare cases wher AWS makes sense. Even for cheap setups like that, bare metal could likely be cheaper even factoring in someone on call to handle issues for you, but the amounts are so small it's a perfectly reasonable choice to just pick whatever you're comfortable with.

That's the sweet spot for AWS customers. Not so much for AWS.

The key thing for AWS is trying to get you locked in by "helping you" depend on services that are hard to replicate elsewhere, so that if your costs grow to a point where moving elsewhere is worth it, it's hard for you to do so.