I use cross band repeat quite often, a Kenwood TMV-71A and Yaesu HT. I have the Kenwood set up to ID it'self with my callsign in code. I use this setup for bike rallys, etc. That way I am not stuck setting in the truck, I can get out, move around and meet people. I have also used it for communications from hospital to hospital. The HT's wouldn't reach the repeater because of the hospital's construction but would reach our trucks in the parking lots. So we crossbanded through the radios in our trucks.
Cross band repeat has many uses.
It also allows me to turn the power down on the HT to its lowest setting so the battery will last all day.
I fully concur. My Icom 2820 required modification (performed by Burghardt) to allow for cross band repeat. This is a minus on Icom's part, IMHO. I probably only use this feature about four or five times a year, but for the reasons you noted, it is worth having, to me. Additionally, if you have a ham friend or family member who is in the hospital and cannot reach the local machine or simplex net from their ht inside the building, a mobile set to cross band can allow them to say hello to their friends and hear well wishes via the cross band link.
I probably most frequently use the feature when bad weather is threatening and I go shopping in the grocery store. This feature allows me to hear the repeater even in the back of the store and to transmit, if needed. The little Yaesu VX-3R works well with this feature.