Eva Buol (asker) Sep 12, 2016:

Thank you Tony for your explanation. I understand much better now !

Tony M Sep 12, 2016:

@ Asker Probably not!

For one thing, in the field of business, 'rate' doesn't always equal 'taux' — generally, only when it is something like a 'failure rate' or an 'interest rate'.

Here, where we are talking about buying shoes, I suspect 'rate' in fact means the 'price' — in many business situations, the 2 terms are synonyms in EN, and we may for example find 'rate card' which is probably the same thing as a 'price list'; we tend to use 'rate' for things like hotel rooms, or other services that do not involve the actual sale of a physical object. However, even in the latter case, 'rate' may be used where it is talking (as here) about the level of prices charged in general, for example 'trade rates'.