There is no question that more people are needing more reliable
connections to the net. With some education, tools, and the right
pricing models, people can be encouraged to get backup connectivity in
a manner that doesn't impact the size of the routing table.
Specifically, they should not announce any routes on their backup
connection unless their primary is down. ISPs should provide
good prices on backups connections (ie, connections that almost
never get any traffic). Contrast this to some ISPs which say you
pay for your connection whether you use it or not. This causes the
customer to want to load balance (and announce all routes all the
time).