Well, if I were writing by hand I certainly won't produce such a code. If I were using a visual editor where I can produce a table and drag columns and rows and make it nice (just like a non-technical user would) such code is produced quickly.
Especially tables can become verbose, especially if the toolmaker wanted to support as many HTML rendering engines (in mail the variety is higher than with browsers) as possible while providing "pixel perfect" results.
Of course 99% of mails doing this, do this for spamy/marketing reasons, not since it brings benefit to the content. (Which is no difference to typography and layout in web or print - brand recognition before content is common)
Especially tables can become verbose, especially if the toolmaker wanted to support as many HTML rendering engines (in mail the variety is higher than with browsers) as possible while providing "pixel perfect" results.
Of course 99% of mails doing this, do this for spamy/marketing reasons, not since it brings benefit to the content. (Which is no difference to typography and layout in web or print - brand recognition before content is common)