there seem to be 2 issues here.. in house vs using a service, and inkjet vs wet process...
Good point.
I own and operate both processes, and offer services to others producing both inkjet (Epson on canvas and fine art papers) and chemical (Chromira, with Kodak and Fuji papers), I also do my own personal printing, most of it inkjet.
A couple of thoughts. First, reading forums like this it’s easy to believe that all large format inkjet printers guzzle ink and are constant headaches and problems, but I don’t believe that’s the norm. Unfortunately the gamut is large, from those experiencing no real issues to those wanting to throw the printer off the balcony. (i’ve owned a number of printers, and will admit there were 2 (1 canon and 1 epson) I felt this way about) Judging by the number of printers we’ve sold and the rarity of complaints and problems I think the norm isn’t nearly as bad as one might think.
As far as in house vs using a service, I think those printing their own work with large format printers are interested in control of the process, including things like quality, convenience, reliability and production time. there are those who think they can save money (which more often than not isn’t the case). Of course saving of money depends a lot on what you are comparing to as well as how much printing you need done.
Regarding inkjet vs chemical prints themselves, technically the quality of inkjet can be better because it provides a substantially larger gamut and advanced dithering and resolution may offer less aliasing and improved clarity. However, these do not often offer an obvious visual quality improvement over C prints produced by a competent lab. Side by side they may or may not be different, but often one isn’t “better” (and many prefer the look of the c print over inkjet).
Other factors of inkjet over chemical printing are paper choices (canvas, textured papers, matt fine art papers), and long term dye stability, inkjet offers far better color stability than chemical prints.
C prints biggest advantage is cost, they are much cheaper to produce, so often are much cheaper through a service than inkjet.
Just some random thoughts.