The problem with ethical shopping

I've been trying to be a purist when it comes to ethical shopping for
camera equipment. It can be difficult. A modern SLR secondhand is
usually only a little less than buying it brand new from an
international seller. Buying secondhand means that there is the least
amount of new stuff made so least materials and energy expended. Buying
from a UK seller means there's the smallest carbon footprint.

But I've been trapped by a problem about a lens I want to buy. I want a
50mm lens. Canon make 3 models. I'm not interested in the most expensive
one though it would be nice to have the Canon 50mm f1.0 or f1.2 L. The
middle option is £200-£400 and it is an excellent lens. The graphs of
the performance of the Canon 50mm f1.4 shows it is close to the L-series
professional version (and the difference becomes a lot less with the
cheaper SLRs I use and with good editing).

However the Canon 50mm f1.8 is a real bargain. It has excellent quality
and focuses fast. It has a reasonably fast aperture to let in more
light. The main problem is the MkII is very poorly made. A minor problem
is the 6-bladed aperture but I'm not too worried about that. The
construction of the elements means there's more chance of lens flare and
stuff too but those are things I can live with at the price point. I've
used two of them and they don't last very long the way I use camera
equipment. This means buying one secondhand is not an option because
there's no warranty. The other option is to buy a new lens with an
extended warranty.

This would be the perfect option because every time the lens broke I
could just get it replaced, but this is not an ethical purchase. First
of all I would be buying something new. More importantly, I know I will
break the lens. The Canon 50mm f1.8 MKII is typical of the cheap crap
which manufacturers make to save money. The construction is plastic and
crappy. I don't use a proper camera bag so I'd end up going through
several replacement lenses in a 3 year warranty period. There is also
the risk of it breaking when I need it. I could miss an important shot.

The option I should have thought of but I just thought of now is the
Canon 50mm Mk1. I suspect it has all the optical problems of the MK2 but
it has a more sturdy construction. I'm not sure how much more sturdy
though. It's also risky buying old lenses second hand since they can
have damage from years of use which may not be immediately visible. This
may affect the picture quality, distort the image or cause mechanical
failure which would mean that I'm still losing out.

So for now I just don't take photos anymore. C'est la vie.