Because nobody has been so annoying to ask that question before
But seriously. eForm has grown from a very simple email form handler and it still contains much of the earliest code. The problem with values in the current version is that there is no difference in received values and any formatted results for email reports. The version I’m working on will keep all values as is (meaning raw php data types) and have the option to format values when required. How numbers are formatted in that case can be set in the configuration.
Until then you’re stuck with it or you can change it in eform.inc.php