Adding anchors

Is it okay to add anchors on a trad line that doesn't have anchors?

Do I smell a Troll?

Depends on, way to many things, such as.....if the route is in a protected area, who put up the FA, is it really necessary, would walking off be an alternative etc.... etc.... etc...

It's a crack in a non protected area. Walk off is possible but we don't own any trad gear and wanted to practice top roping the line

So you're talking about a gear-protected, single-pitch route, correct? Presumably near other routes? Just for clarification...

Yes it can be protected by trad gear and walked off. The info on the route says build your own anchor once ontop and have belayer follow clean the route. There are no other routes within 40 feet of the crack. There are also no boulders, trees, shrubs up top to setup an anchor.

All I wanted to do is drill and set two bolts at the top so the route can be repelled down and top roped.

Sorry but no. If you don't have any gear or your friends don't, I would highly doubt you have done much if any bolting. To put anchors up for a TR you would most likely put them on the face so the rope is not running over an edge and wearing the sand stone, which you would need to build an anchor to lower over the lip to bolt it. I won't even bring up the fact that it is an established route in a guide with a given description and decent. Or the fact that you have sought out the advice of MP rather than done the proper thing and contacted the original FAer. I have nothing against TRing a route but if you have to drill your own anchor to go it, go find a different crack or borrow/buy gear and learn to lead or make your own anchor.

A huge majority of the routes on this crag are walk offs and 80% of these routes have the anchors on top anywhere from 6 inches to two feet from the face...

Only after consulting with FA crew!

What is wrong with TR a route from the top? You do not need to sling shot a route to TR. The crag I learned to climb at that is how all the climbs were initially climbed. So buy some gear and learn how to set an anchor and TR from the top like the guide suggests.