If I remember my microeconomics correctly it's called Type I customer
discrimination.
If the price for a product is the same for everyone (picture the two
intersecting diagonal lines representing supply and demand), you will get the
supplier's income represented as a rectangle defined by the origin and the point
of supply/demand intersection. The two triangles immediately outside this
rectangle represent consumer and supplier surplus. Consumer surplus is where
people would have bought the product anyway, even at a higher price.
Suppliers have a few methods at their disposal to reduce this consumer surplus
to more efficiently extract profit. One of them is to change the price based on
the customer's willingness or ability to pay for their product. They could
conceivably do this by polling each customer before purchase as to their income
or willingness to pay, and then charge each individual the maximum price they
would tolerate. Another, less efficient, but more practical method is to force
customers to self-select based on their desire for convenience. Grocery coupons
are a good example: poor(er) people find it worth their time to cut out coupons
from the paper, and rich(er) people just can't be bothered with it. This
generates two price points instead of one, which allows suppliers to take away
surplus from you, the consumer, to directly increase profit. Consider the
"inconvenient/obscure extra download" your very own coupon of sorts, a Type I
customer discriminator. This artificially created inconvenience means rich(er)
people pay more, and you pay less.
HTH,
Bob
