When Andy and Danny go to paint the caribou in the tent, you can see them carrying three buckets of paint - red, green, and yellow. When they finish painting, there are some drawings in purple paint. But no combination of paint that they brought would have created purple, and they didn't bring any with them. So where did it come from?
When Andy remembers when Mayor Roth and Mayor Simms played a friendly game of golf, Danny replies it wasn't so friendly. This is probably referring to the season 2 episode "Fore!"
In this episode East Gackle celebrates it's 100th birthday, but in the episode "Life is a Lottery, Old Chum" Andy says it was the 75th anniversary of the founding of East Gackle. That would make it 25 years since that episode, but everybody is still the same age.
There is a person who looks like Leech's dad sitting on the benches. If so, this is the second time we have seen him.
There are two people who look like Danny's parents in the pancake line. If so, this is the second time we have seen them.
In the flashback when Andy remembers the golf match between Mayor Roth and Mayor Simms he is wearing his normal clothes. But in the episode named "Fore!", when this happened, Andy is wearing clothes of a caddy.
Andy: We've got to find someplace to hide it...permanently.
Danny: You sound like you're in the mob.
Andy: I've never killed an animal before, I like animals, heck I've got one for a sister.
Andy: If I was wearing better shoes, I might have run with you.
Andy: Mom always said its all fun and games until someone loses an eye, but she never said anything about a caribou.
Danny: They're gonna see the caribou is painted.
Andy: Uhh...they're gonna see the caribou is dead.
Mayor Simms: So pack it up and say, bye bye caribou.
Zoo keeper: Bye bye caribou? Ohh...I mean yes sir.