Throughout our "FARM", there are very mature large trees everywhere and the lines are made of clay and the roots can crush the sewer lines. 

Do they see it because of the brand or because they believe Walgreens will only set roots in "A" locations and the Bojangles of the world will settle for "C" locations?

Steve would have had the ability to settle down his roots here instead of being priced out of the NYC location.I know Investors tend to think of only in terms of Today and find it very unpredictable to think of tomorrow, but please remember that even Squirrels think about tomorrow as they put away their Nuts for the Winter.

I again got a plumber out and he unclogged it and found roots in the main pipe from the tree that was cut in the front yard. 

I am not a New Yorker, but have family roots there.  

I had children and needed to grown thicker roots for a bit, so took a hiatus.

We did one built in 1830The years of plumbing retrofits & the tree root infested sewer pipe was a nightmare !!!

Marie Poe says here.Only thing I would add is that we train our CFK folks to do the following:1) Make contact as a wage earning employee representing a small group of investors (this curbs their likely disdain for large banking institutions).2) Try to get to the root of their problems before demanding they leave or offering money.3) Try to offer assistance instead of money (moving van, able bodied workers).4) Try to offer less money instead of more money.5) Follow up diligently to ensure any CFK agreement is adhered to strictly.6) (As others have suggested) Concurrently file initial UD action along with the CFK negotiation, so you are able to carry a big stick while also speaking softly.If you're able to do all of these things, you should be pretty successful in occupant disposition.

I live in an area where tons of houses end up with roots in their underground pipes.One pipe has had recurring problems and Roto Rooter is suggesting installation of an outdoor clean-out (since the house's current one is small and insufficient).It involves excavation and the RR guy says that, unfortunately, he's not 100% sure whether the problem pipe is inside the house's footing (under the house) or outside the footing (and accessible with an excavator).

If you approach him with a real concern for HIM, then you'll get to the root of the issue.