How do some Dealers Sleep at night???

I mainly collect Mercury Dimes. My wife & I used to travel to a lot of big Coin Shows, as a vacation & to look for my Mercs... 10 years ago, "mainly Dealers" talked down about what they called Slabbed Coins, so I always bought Raw ones... Now I understand why they did that.

I've recently decided that I wanted to get my Mercs graded & started sending them in to NGC. The disappointing fact is... 20% of all the Mercs I sent in, came back as Improperly Cleaned.. What a Coincidence! All of the improperly cleaned Dimes were more Key Coins (Expensive) So I too, have been burned by "Some" Unscrupulous Dealers.. How do they sleep at night???