Is this reasonable cause?

My clients are my clients because they don't file and they don't pay. They are not the problem

Your clients are illegals, in other words. So you are saying that there are some laws that can be broken at will and "not [be] the problem", but not others? How are we to know which is which?

Hahahahahahaha

The IRS, and all of us, should love the late-payers!! Not only does the government collect the full tax, it gets a good interest rate (compounded daily), along with penalties computed using a penalty rate. If any business could pull this off with its customers, please PM me as I’d like to invest in it.

Banks don't make money off people that pay everything on time. They make billions on late-payers. Same principle.