I think the hole is actually like the slugs nose that they breath through and they have the ability to close it if they want. Perhaps you don't notice it as much on the smaller slugs. (It is best to leave it alone I suppose, lol)
I'm certainly not an expert in trading but it is a fun hobby that has been rewarding for me without doing a lot of volume. There are ways to minimize fees and mine coins on your computer. There are many different ways of trading and making crypto but I think it does get harder if the market is going down.
I am doing it from Canada too and that has a way of limiting things:)