It's funny you mention this. On a somewhat related matter, I'm seeing ridiculous stuff on a grand scale when it comes to government travel. Say you have to travel to Europe for five days on business. You start to look into booking your flights, and you see that if you fly on a Monday and return on a Friday, you pay $X. If you travelled on a Monday and returned on a Sunday, you could get a flight for $1600 cheaper, but would have to deal with a couple of extra nights in a hotel. Even though you'd be saving the government money by travelling on Mon/Sun and taking a couple of days of personal leave, it's not allowed. Not even if you paid the hotels yourself. Supposedly it's now "Misuse of a TAN" (Travel authorization number).
Optics.
If you want to mix personal and business travel, what's supposed to happen (apparently) is that the business travel gets booked, at whatever cost. Then, if you want a couple of extra days, you contact the airline, pay them the fee (out of your own pocket) for changing the flights, and then pay any extra (if any) on the airfare if the flight becomes more expensive. What that policy doesn't take into consideration is: What happens if they flight becomes cheaper as a result? I'm sure Air Canada will be banging on the door of the keeper of the Consolidated Revenue Fund saying "Cpl Bloggins just saved the Crown $1600 by taking two days leave and changing his travel dates. Here's the Crown's $1600 in airfare savings back!". Yep, I'm sure that'll be happening. ;D