Now, could you inspect transactions and try to make a guess at whether they're conveying data through a side channel? Perhaps. But it would be an unreliable guess. For example, the presence of .01 transaction, made to a particular address at a roughly particular time, could convey significant information. Is 2.71828 a high-entropy amount, or is it just an estimate of e or a result of an exchange-rate conversion? Etc.
Why on earth would anyone use e
as an amount for a monetary transaction ?
You are right about exchange rates conversion, though. I've just realised it. So you have a point.