Lol funny picture, they are lactose intolerant, so maybe he had to much.
Dreamworld does walk adult tigers through the park, guests can pay and walk with them and get photos and all that sort of thing, but those walks take place prior to the park opening so no danger to guests there.
the tigers walked through the park during the day are the 'cubs' their walks started when they were about 2 months I think from memory and they are still going these days, they are over a year old now maybe 2 or 3 I don't remember when they were born, but they are female Sumatran tigers, females aren't as big as males, and sumatrans are nowhere near the size of bengals.
The keepers do a good job, they know their animals well and there's always two keepers walking the tiger, one on either side of the shoulder, quite close together to prevent deviating from the course they are walking on, and all guests only get to pat them from behind. obviously patting is up to keeper discretion anyway and if the tiger was antsy and decided to drop down they'd stop all pats until it settled down and was on its way again.