Self-sufficiency (which requires at least enough carrying capacity for a day's worth of food, lots of water, cooking gear unless you like not having a hot meal at the end of a hard day, a shelter that will reliably keep you warm, dry and comfortable, and enough clothes that you can stand to go for a week or more without washing them) is what makes spontaneity possible. If you always have to rely on there being somebody who will take you in, that means you always have to plan your days around ending up in a town, not to mention budgeting several hours for hanging around pathetically, hoping someone will invite you into their house. With the camping gear, you can just set up a wild camp in a field or forest somewhere, cook up a hot meal, and get up the next day to go whatever direction you feel like without being concerned about where you end up.

Trust me. Having more stuff is what allows you to be spontaneous, not what prevents it.

As others have said, instead of asking for the high-end road bike, get a $1000 bike, which will still be of great quality especially if you know what you're looking for, and put the rest of the money toward ultralight, high-quality camping gear. Your load will still be pretty light, but you won't have to structure your trip around where you think you can find people that feel bad enough for you that they let you sleep in their house. You always have the option to couch-surf, but giving yourself the option to camp just makes sense if you're not going to pay for hotels.