AK missed flop, get it in?

[Graham C]

Is it generally standard to ship it in with AK on a missed, not too dangerous board? 

For example

mid comp,

Board   

If you check and then are bet into, are you getting it in with AK here?

I seem to be being called a lot at the moment with AK like this, but I'd personally be laying it down now.  Am I being too nitty or is laying down the right thing?

tyvm

[gatso]

err, depends on about a million things

stack sizes

oppo

did you limp, raise, rr or call a raise pf?

etc, etc, etc

[GreekStein]

stack sizes are most important here though if it somehow commits you maybe you should just be shoving pre

[pokerfan]

bet fold

[gatso]

is it AKblue?

[Graham C]

AK off!!!!!! (red and black)

Blinds 250/500/antes
Me, about 6k now, having just doubled him up, him about 5k.  Folds to him in the small blind, he min raises to 1000, I call with J9 green.  Flop, J high (as above) he min bets the 500, I shove for the rest, he calls with ace high.  

This isn't a thinly disguised bad beat btw, it seems to be happening a lot that people are calling me for their entire stack with AK on a missed board.

Reason I shoved - last time it was my bb, folds to him on the small blind, he calls (200/400 then).  He was playing 2.8k, I was on 9ish.    I raise it to 2.4k and he shoves for the 400 extra - he's got JTo and hits a ten - fair enough.  This time I figure that I have actually top pair here, I'm shoving to protect it, if I'm beat, I'm beat.  

What I can't understand or work out is why a) in the first hand (JT) if he was going to lump it in with shit, then why didn't he just shove/raise preflop?  It's not like he was trapping, but he was short, so why not just get it in and hope I call or at least steal the blinds.  The AK hand, why lead out for a min bet?  It wasn't even c-bet amount, he's asking to either be flat called or shoved on.  He hasn't got a hand yet that he wants people to call or shove with.  With ace high, I generally either try to take it with a cbet or give up if someone is shoving strength.

Is my thinking wrong?