*sigh* With regard to units...
... it is not a conspiracy from drive makers to diddle anyone, nor is it ISPs misleading consumers (about the maximums anyway).
Kilo is an SI prefix and it means x10^3 (i.e. x1000). It has never and never will mean x2^10 (i.e. x1024). However, for the purposes of Computer Science, it is convenient to abbreviate x1024 as 'k' even though in fact it is not. This is not about misleading but simply jargon, since programmers, hardware designers and so on understand that working with binary means that you reach 1024 when you fill a ten digit memory location with ones, but this is still close enough to 1000 for k to be a useful and obvious shorthand.
The problem came with Microsoft, who erroneously report drive size as if it should be calculated based on a kilobyte being 1024 bytes, a megabyte being 1024 x 1024 bytes and so on. The drive manufacturer did not cheat you at all, Microsoft just can't count and/or is ignorant of the units it is quoting.
Communications specialists work in terms of bits per second (b/s or bs^-1) as this is the SI unit of data throughput (bandwidth). 8 Mb/s is 8,000,000 bits per second and not 8,388,608 bits per second (8 x 1,048,576 [1024 x 1024]). Note, this is still bits and not bytes per second (B/s), hopefully I don't need to explain a byte.
As a result of this confusion and the compounding stupidity, the IEC recently introduced the kibi (binary kilo, ki), Mebi (binary mega, Mi), etc unit system. These operate on a base of 2^10 as the unit progression rather than 10^3 and actually are convenient for Computer Scientists but still often incorrectly used or poorly understood, as yet.
Unfortunately, even allowing for this, the gimp that your ISP employs on helpdesk, customer service or sales probably doesn't even understand that bit and byte are not interchangeable, and that one is b and the other B, let alone that k/M/G is not the same as ki/Mi/Gi.
In short, the ISP is offering you "upto, subject to our fair use, distance from exchange, yadda yadda" 8,000,000 bits per second when they offer you an "8 Meg" package, not 8 MiB/s which would in fact be a "67.1 Meg" connection.