Due to abuses by a small few, here in the USA we have similar travel rules that limit what we can and can not do on military travel: no first class, have to stay at places at the military rate, have to book travel through a contract travel site and get fares at the contract price (even if I can get cheaper, more convenient flights off the internet), have to use my gov't travel card for certain things (folks using the automatic tellers at casinos and strip clubs to get their per diem cash are the latest scandal), have to use small rental cars, have to get multiple approvals for conference hosting, etc. etc.
The good deal boondoggle is getting harder to come by and requires careful planning....