If you are willing/able to do some long days (and remember you may be facing a head wind all day) it's been my experience you can tour in the US w/o camping. Conversely, there are some days you will look at the map and do a much shorter day then you like because theres a hotel at 35-40 miles and then the next one is another 90 miles.
I've never done the ST but my first 3 tours were the WE and picked up the TransAM in Co and on to Va., Great Parks North & South bridged by the TransAm route between and the Sierra Cascades route. For those 100± days on the road I camped a total of 1 night when a storm blew in when I was going over a pass. But there is 3 or 4 days mixed in to those trips where I really felt I was in trouble, still out 30 - 40 miles from the next town and I was already completely beat. And I made it 1.....pedal.....stroke.....at.....a..... time.
For those first 3 trips I just carried an emergency bivy. Now I carry the lightest tent & sleeping bag I could find. I still rarely use them but the weight penalty has been worth the peace of mind.
Also, someone else mentioned a budget of a $100 a day and I believe them but I've never been able to do that on any of my trips, I'm probably at 150. The caveat is I consider these trips as a treat and if I go into a town and there's a nice restaurant & a Subway, I eat at the nice restaurant. Or there's 2 hotels and 1 looks pretty frayed, I'll stay at the nicer one.
One last thing, do some homework about whats going on ahead where you plan to stop. At the end of a 100+ mile day I pulled into Brea Ky on the Friday night start of the Brea Bread Spoon Festival(?). Every room in town was booked. I finally found a room in one of the worst places I ever stayed in.
Pete