It strikes me as a judgement call.

On one hand, it can be argued that some people have no concern for others. And you cannot pigeonhole them by nationality or socio-economic stature.

On the other, the woman had a legitimate medical condition that required treatment, even if the treatment was unpleasant to those around them.

I do not know why they were travelling, and whether it was discretionary (at which point she should have considered whether or not taking the trip) or mandatory (in which case she had little choice).

Mind you, putting her feet on your armrest is a definite no-no, regardless of the reason.