Kate, a lot of clients are very naughty and do ALL SORTS with their nails that they shouldn't, they use cleaning products and bleach without gloves, they wash up and clean the oven without gloves, jeepers, of course all those chemicals are going to be responsible for problems with the nails . . . some clients are religious with their oil, some fib a bit, and yes, you can see the difference between the people that use their oil and the people that really don't.
In fact the "line" I tend to use when selling cuticle oil is that it will "make your nails look better for longer" , because it's true.
There are quite a lot of mobiles and salons round my way that do exactly what you are doing though, apply white tips, let them grow off, and do a new set. A lot of clients who now come to me for rebalancing instead of constant removals and new sets have told me this, so please don't think you are alone in what you are doing, you are not. :hug:
Applying the white gel or acrylic is a harder skill to learn but can be mastered (and charged extra for), and these nails tend to be stronger, mainly because with white tips you don't blend them