A townhome is a style of home - generally more than 4 "stuck together" in a row (but not always). Condo is a form of ownership, and while they are most commonly garden style, midrise or hirise "apartment" style homes, they can even be single family homes or taken on a townhome style. In fact, in my area a "2 over 2 town" is a common condo style right now... it's a 2 floor townhome, with another 2 floor townhome on top of it, with several of those stuck together side by side.... and they are owned via a condo style ownership.
The difference? "Fee Simple" ownership is how most people own land, single family and the majority of townhomes. They own it all..inside, outside, the earth it's attached to, what's beneath the earth, the space above it... it's all theirs. If it were condo style ownership they would own only the inside of the home.... not the roof of the building, not the ground below it, nada outside the home.
I am not sure I understand the other questions but I will give it a shot. Renters are frowned upon because they don't care for the property like owners. FHA and VA also have restrictions of the number of investor owned units that can be in a building/project. So, too many renters=inability for many buyers to purchase=reduced value of the home.
Hope that helps.