I wonder if they use your national settings when you are logged in.
That would explain some bids
I myself have my own standard halfway between US and European notation, and I know internationalization issues are often overlooked by developers :blush:
It'd be great to choose notation based on the national settings, as you said. The simplest 'compromise' would be not using commas/periods for transactions e.g. "1000490 USD" instead of "1,000,490" or "1.000.490"