Instructions ‘to minimize swallowing use a pea-sized amount’ written on a toothpaste tube bought in DC airport.

The extent to which there is a cross-cultural understanding of what constitutes a pea sized amount. Is a Bolivian pea the same size as one grown in Maine? Are there any cultures where peas are not grown at all making it more difficult for that user to accurately squeeze a pea sized portion?

And, looking ahead the ability to personalize and individually target instructions using language appropriate to that user.

Given that it is easily feasible to create a dispensing cap to accurately pop out pea sized portions of tooth paste why isn’t it included with this product? Who are the likely users of this product? What is the cost of squeezing a bean (more than) split-pea (less than) the desired amount?

Related: the motivations for writing instructions/signs and the likelihood that these instructions will be followed here.