Watching that twitch clip via mobile, I might not have read the correct energy burn (small writing) but looks like 19+80=99 energy an hour to run that autoloot passive (pet+buff burn).
So it's going to burn a ton of bars whilst active. Which increases the hunt input ped which in turn correlates to xp gained. I'm still pretty convinced cost is returned (maybe just TT, maybe more).
I'm also pretty convinced that the passive gain, grows at a faster level at each level gained. Which in turn somehow reflects in loot returns.
I suspect there are not many +50 top end (high burning) pets in game (yr 2014+ pets) Although I notice some interesting returns around level 50 (more level 51), take it near 60 and it gets quite interesting indeed.
It actually does me no favours to report this, I quite like food price at 136% rather than 300%. I also mainly run a 20% skill gain pet, so additional skill gain could be a factor at higher pet levels, which in turn is highly likely to correlate to returns.
You'd need to run a top end pet over level 51 to see for yourself. You're probably looking at good 500k xp though. That takes a while.
I know some pink rabbits got some decent loots, although if i remember the streams a while ago, they were still babies.. level 30's. Those Ark moon pets burn at a high rate, so they will rock at 50+
Anyway what works today, can change with the flick of a switch. My trust on moving goal posts is one of my pet hate in game (excuse pun).
I base this on my personal experiences. I was doing quite well out there before this robot event kicked in. In fact I so trust my 'working' pet (I.e. it has a job like a farmers dog), I dont have much faith doing anything else.
Maybe that's the 2% - 5% you guys are looking for
If people ramp the food the prices. I'll keep my mouth shut in future
it wont take me long to find out how a pet performs at level 70.
All the best
Rick
Ps edit: I've not got one of these pets. My main pet runs at 17.90+54 energy an hour (Royal Chirin). I simply dont have the heart right now to put 4 more years into a brand new pet. Although if you do, I'm sure it will reward you.