Big dollar bike shoes are as much a fashion accessory as a necessity and are aimed at competitive riders where weight and great stiffness are important.Big dollar shoes are not necessarily a necessity on a bike tour.
On the Nashbar website they have six shoes which take SPD cleats for $29.99 or less. Before using a 20% off coupon Nashbar frequently has. On the Amazon site the Crocs shoes are about $25-30. These are official Croc brand shoes so they might be much more than the copy shoes sold in flea markets. $30 or less for a pair of shoes does not meet my definition of "Big dollar shoes". All of the $29.99 or less Nashbar bike shoes looked like sneakers so I would guess they are comfortable.
There are plenty of well made, comfortable and fully functional road and MTB type shoes by well known manufacturers available in the $100 or less range, sometimes much less if having the latest color or "style" and the most advanced technology aren't issues.