Look at rides like CANDISC and BRAN. They are not expensive.

Some organized tour have a fundraising component, like Cycle Oregon and Adventure Cycling Association tours.

REI tours cater to people who want a "high-end" experience. Check out Backroads. Very pricey.

As Rowan points out, there are costs you are not considering. The comparison to an all-inclusive vacation resort is not appropriate for obvious reasons.