AOG
You haven't provided a causal link between ethnicity and the tendency to fly tip.
In my previous job, I had to travel up and down the country, and what I noticed was that there is a correlation between deprived areas, and litter.
Where an area is 'rough', or has a high proportion of economically disadvantaged residents, you will observe much lower levels of civic pride. This is not determined by the racial mix of the population.
I do not think your conclusion is valid. It seems to be an assumption based on now criteria, and that is very flawed and simplistic.