Reactive, me? nah!

Took Reggie to the vet today to get his bum squeezed again
The vets we use is at the back of a large pet store,
been dreading it all week the way he's been reacting towards other dogs recently.
It's a no appointment neccessary type place, so it was OH's idea to arrive as the doors opened to avoid the crowds! Bad idea...
everybody else obviously had the same idea, and we pulled up to see three dogs already waiting outside.
Approached slowly expecting the worst....and nothing, Reg didn't bat an eyelid couldn't believe it....sat in reception within feet of four different dogs, one owner with a Springer lengthened the lead to let her dog sniff Reg but I warned her it probably wasn't a great idea, explaining he looks friendly but then goes in for a nip, but I'm pretty sure she thought I was making it up!
As a treat after his 'procedure' we took him to the lake and BAM! back to normal.
I don't get it?

Casper can be like this at the vet. Guess its a place they rarely go to and perhaps feel too unsettled at to be reactive.

That was all I could come up with, he didn't seem too stressed, but I can't think of any other explanation.

Aren't they a mystery?!

Look at the set-up/situation and the differences for clues.

My collie reacts to head-on approaches with eye contact more than anything. Also boisterous dogs he finds alarming. If I go to join some dogs approaching from behind he feels safer. He can't handle dogs straining on a lead either.

Benjie doesn't react (but acts dominant) to dogs inside our house or in the garden - yet take them him out on the street and it's a whole different story. There are only four dogs he has got on outside the house and garden - in 8 years of owning him (OH not me)

They are a mystery sometimes... and when they're like that I wish they could speak English.

That's interesting. Do you think it's because he thinks you have accepted them if they are allowed in the house or garden? Or does he just feel safer at home?

You have a point there, Reggie & Maggie are much better if the dog is on the other side of the road walking the same way than if it's coming towards them.

Maybe Reg could sense fear on all the other dogs in the vets and it was a case of them all knowing they were in the same boat, all to preoccupied with what was going to happen next? who knows?

flooding, common phenomenon.

Which presumably doesn't work helping their issues if the dog goes back to normal five minutes later?

Would 4 or 5 dogs be considered flooding then?

I still can't work out what the situation is with Polo at sheepdog training. He did not react the first time I took him. He saw the dogs before the sheep and we have sheep but he will still react to dogs in the next paddock. But he has never reacted to any dog there.

I have all sorts of theories but quite honestly he is a different dog there and I am so curious as to why.

Any ideas?