Keyword Structuring

Bidding on a phrase match of "masonry" does make bidding on other phrase match that contained "masonry" unnecessary ONLY if you are placing them in the same ad group.

My guess is he is looking for more traffic to scale it up.

In this case, he should put the phrase match "masonry" and add exact match negative keywords like "company" and "contractor" on a ad group level to find more converting masonry keyword to phrase match and place the rest of phrase matched keywords in other ad groups respectively.

I used to have all 4 keyword groups inside 1 adgroup

Exact
Phrase
Broad
BMM

since Adwords has changed how exact match keywords work I no longer add in Phrase keywords as Exact and BMM will cover them.

From Google:
"Phrase match allows your ad to show only for searches that include the exact phrase, or close variations of that exact phrase, with additional words before or after.
• Example: "adopt a kitten"
• Searches that can match: adopt a kitten, adopt a kiten, how to adopt a kitten"

Here are my 2 cents on why the advertiser is doing so:
1. Targeting keyword "masonry" in phrase match: The advertiser wants to show ads on all those search queries which have the term "masonry" in them
2. Targeting keywords "masonry company" "masonry contractor" "hire masonry company" all in phrase match: The advertiser in this scenario wants to show ads on all those search queries which have the specified terms in the exact same order.
For eg: "masonry company" will show ads on "find masonry company nearby" or "masonry company for hire". Here the advertiser is more interested in targeting the keywords that follow the specified order which will not be the case with just "masonry" as it may show ads on "company that offer masonry" or "company offering masonry near me" etc.

Now having keywords like "masonry company" does improve the ad relevance & expected ctr components of the quality score for the search terms like "find masonry company nearby", which impacts your ad rank thereby giving you better ad positions in less cpc. In short the more closely related your keywords are to the search queries the better the quality score & ad rank.

It again boils down to what is the business goal of the advertiser and how they tailor the keyword/match type structure suiting it to their business needs.

My advice would be to run a search term report for last 30 days and analyze exactly what search terms are triggering the ads and adding the irrelevant to negatives(again here a choice of negative match types can be made based on what keywords you want to exclude - use them smartly) and adding the converting terms in exact match, or create match type based tightly themed ad groups with cross negatives to avoid cross triggering etc.