I feel this may a common accusation that those of us with ASD/HFA have to deal with, that neurotypicals will call us "lazy" due to misunderstanding our "default operating system" or based on unwillingness to openly discuss the reality that we're impaired in emotional-intuitive faculties (as mental disorders are big-time stigma/taboo).
So using the "lazy" label becomes a more emotionally palatable and convenient label for them - the paradox is THEY'RE the ones being lazy for not wishing to probe any further, they just want the path of least analysis, the explanation that's the most "comfy" for them
I believe this pejorative may come about for a variety of reasons...to think of a few:
1) From a large percentage of ASD folks being chronically unemployed, or under-employed;
2) People passing value judgements that, by a certain age, you should have certain behaviours under control or "mastered" like a normal person. If you don't, it's because you didn't "try hard enough".
3) IN some situations, like in the workplace or even as adult living with (step-)parents, you may be assigned a task and then ask them for clarification e.g. "When you ask me to do X, does that mean I also need to do Y?" - some people may interpret this as subtly defiant, or passive-aggressive, or that you KNEW that OF COURSE it bloody means Y as well, a "normal" person would have intuitively have known that, ergo you must be lazy
When more objectively speaking, NTs need to more clearly communicate as it's a two-way street.
4) When you make silly mistakes that go against the grain of "common sense"; but again, sometimes these events contain a good dose of irony b/c often (at least I've found) I expended MORE effort than what they were expecting, not less, yet sometimes they may still throw the "lazy label" at you out of that convenience we talked about (i.e. this way, they don't have to concede the reality that you have a mental disorder, b/c at least laziness isn't a mental disorder so it's not a taboo topic).
5) Based on what psychologists called "learned helplessness", or the fallout of the victim mentality and precursor to passive-aggressive personality: NTs may give us advice that seems lame and we retort with "tried that, didn't work" or something of the sort.
Another trigger for the "lazy label" may be the fact that us ASD folks frequently feel exhausted from trying to process the channels of communication on a daily basis on reconcile them to an accurate message that we accurately respond to, and then dealing with the angst of ridicule and contempt that follows. I read something like this on Quora recently.