Holy shit man if i were you i would simply accept that i fucked up and hope people forget about your stupidity.
Pounds is the imperial unit of mass
The troy pound (373.2417216 g) was made the primary unit of mass by the 1824 Act; however, its use was abolished in the UK on 1 January 1879,[27] with only the troy ounce (31.1034768 g) and its decimal subdivisions retained.[28] The Weights and Measures Act 1855 (18 & 19 Victoria C72) made the avoirdupois pound the primary unit of mass.[29] In all the systems, the fundamental unit is the pound, and all other units are defined as fractions or multiples of it.
https://en.wikipedia.org/wiki/Imperial_units#Mass_and_weight
You are right when it comes to the slug, its also mass.
In fact it just shows how outdated the imperial system is that it doesnt even has a unit of force at all.
So basically what you are bitching about the metric system is what happens with the imperial system.
Metric system has its own unit of mass and force, the imperial doesnt.
As to why people use mass instead of newtons? because for mass was standarized based on weight, when people decided to create a unit of mass they used weight.
For 99.999% of the applications out there people use mas and weights interchangeably because we are all subject to the same gravitational pull.
Thats why in a lab you use a scale (measures weight) to determine the mass of reactives.