Preferred method with IBC is a suitable Fork Lift Truck.

Regarding slinging IBC's there is potential for these to turn turtle through the sling (been there, seen it) - after nearly losing a second during a trial evaluation we used spreader straps to stop the slings closing in but after the trial ensured the chemical and its permanent dosing system could be serviced by FLT.

Can't the delivery company use a Moffat (The small FLT that travels on the back of the waggon)?

I've actually done that job in the past, delivering 1 ton containers of printing ink, using a hiab. Horrible job, as the load is often likely to turn turtle, this is true for clay roofing tiles too!

The company getting the delivery really should invest in a forklift truck. 

I presume once the delivery is completed you have workers move the IBC around the work area, so wouldn't a forklift truck (FLT) be a safer option than a pallet truck - as pallet trucks tend to play havoc with manual handling, by causing back aches, arm strains, etc., and that's when they are actually working properly. 

Incidentally, there is a new product now, a Remote Control (RC) forklift trucks.  I think Palfinger makes a version.  Perhaps you could have a RC FLT at your company rather than a normal sized FLT, it might be cheaper in the long run.