It is better to buy hardware with support for free software in mind than
random hardware. Any given random laptop (even from companies who support
GNU/Linux in general although are not necessarily free software focused) will
frequently only have proprietary drivers and/or simply lack support for
certain features. Some of the advantages of free software where it is
actually free in whole and not just in part is that other developers can
contribute and generally work with integration and enhancements. Upgrades are
generally smoother and less problematic, etc.
This all extends beyond theory. I see it every day at various levels. As an
example there are game development companies which are improving the support
for Intel graphics drivers. While hard core gamers may not find Intel
graphics sufficient the majority of users are getting more out of them than
they ever could have had the graphics been dependent on proprietary software.
So not only are the free drivers better supported (don't miss out on certain
features due to incompatibility with the free software development model),
better supported across distributions, etc they are better optimized too.
Some of the best supported wireless chips are another good example. I've
frequently heard people describing these chips as "magical". A humorous
statement considering the difference between these chips and others is they
are supported by free software.
