Why have profits and prices gone up and wages not kept pace?
There are many reasons.
One of the reasons is that decisions about investment and allocation of resources are made using profit potential is the dominant metric. This has been true for a very long time, and certainly has prevailed since the beginning of the industrial revolution and modern market driven capitalist economics.
With this metric there must be a market that supports prices that are higher than costs, and the costs must be minimized and this means that payroll / wages for workers are minimized. Investments get made when price minus cost shows there will be a profit ... but there is no equivalent calculation available for workers and their decisions about working.
Legislation about minimum wages and work place conditions do not change the underlying market forces. It is not at all clear whether macro-economic conditions drive micro-economic decisions or vice versa ... but it is clear that there has been a lot more success for for-profit companies during the last fifty years than there has been success for their workers!
GPA (Global-Payroll-Association) report for 2017
Among the biggest challenges that many global and in-country payroll professionals face are the sheer complexity of local regulations and a lack of access to a single international payroll software system to help automate such complexity away ... But times are now starting to change.
A Living Wage in Australia’s Clothing Supply Chain ...
Estimating factory wages as a share of Australia’s retail price
'http://truevaluemetrics.org/DBpdfs/Wages/deloitte-au-economics-living-wage-australias-clothing-supply-chain-291017.pdf'
USA ... Annual Coal Mining Wages vs. All Industries, 2013
'http://truevaluemetrics.org/DBpdfs/Wages/Annual-Wages-by-State--Coal-Mining-vs-All-Industries-2013.pdf'